Recent years have witnessed ever increasing quantities of beverages, such as beer, carbonated soft drinks and juices, being packaged in amounts of up to 12 ounces in metal cans and particularly in metal cans with ends that include a score line defined opening panel therein to provide implement free access to the contents. Such opening panel containing can ends are generally called "easy open ends" and include variant basic constructions of a first type wherein the score line completely circumscribes the panel and thus renders the panel completely separable from the can end and of a second type wherein the score line only partially circumscribes the panel to render the latter only partially severable from the can end and to thus remain in attached relation within the can after the pouring opening has been formed. As mentioned above, such opening panels are conventionally perimetrically delineated by score lines of decreased metal thickness.
In order to extend the use of such easy open can end constructions to larger volume containers, the art has suggested the utilization of a cap assembly to close and reseal the opening defined by such score line defined panel. Among the objects of such cap utilization are a re-closure of the container to prevent loss of liquid content and a resealing of the container to limit further losses of the dissociable gases, i.e., the "carbonation", in the remaining liquid contents. U.S. Pat. No. 4,580,692 discloses one construction for such a resealable closure cap assembly in association with a selectively contoured can end construction to cooperatively accommodate such resealable closure and to retain the advantages characteristic of the "easy open end" construction.
The provision of commercially acceptable resealable easy open can end constructions for larger capacity beverage containers requires in addition to the functional features of present easy open ends both sealable retention of the can contents and accommodation by the resealed cap of the inherent pressure buildup therein. Also required is a can end configuration at the pouring opening to accommodate the displacement and disposition of a resealing cap into and out of operative relation with the pouring aperture therein without diminution of the convenience and cost effective nature of the basic easy open end constructions during manufacturing, filling, shipping, selling, and consumer usage thereof. At least a portion of the cost effective nature of easy open end can closures is attributable to the preliminary fabrication of the end closure and the automatic sequential feeding of such end closures into operative proximity with the open end of a filled can and subsequent hermetic connection therewith by a conventional "double seaming" techniques and machinery. The addition of a resealable cap assembly to the end closure requires accommodation of problems not heretofore met in the basic easy open end constructions conventionally employed in the smaller capacity beverage cans.
Experience to date with the resealable cap assembly and can end construction disclosed in U.S. Pat. Nos. 4,580,692 and 4,648,528, the disclosure contents of which are herein incorporated by reference, has indicated a basically antithetical relationship between the need to mount the generally resilient and flexible resealing cap assembly on the end closure in such manner as to permit its displacement into and out of sealing relationship with the pouring aperture therein and the need to positively and securely fix the position of said cap assembly at one predetermined and uniform location prior to, during and after securement of the cap assembly to the end closure, through the "double seaming" of the end closure to the filled container and during the subsequent handling and stacking thereof.